When President Donald Trump and Canadian Prime Minister Justin Trudeau met at the White House on Monday, the issue of a possible border adjustment tax did not come up, Canadian Finance Minister Bill Morneau told CNBC.

"What we talked about today is the foundation of a great relationship. We talked about how the two countries work together today and we talked about how we can expand upon that relationship. We didn't go into the details of our respective tax regimes," Morneau said in an interview with "Closing Bell" on Monday.

Republicans are pushing for a border adjustment tax that would tax imports and exempt exports. It is part of the GOP's overall tax reform package.

While it wasn't discussed at the meeting, Morneau said, "Our sense is that a border adjustment tax wouldn't necessarily enhance our trading relationship."

The president has been critical of the North American Free Trade Agreement, which helped make Canada and Mexico crucial U.S. trading partners.

"We have a very outstanding trade relationship with Canada. We'll be tweaking it. We'll be doing certain things that are going to benefit both of our countries. It's a much less severe situation than what's taken place on the southern border," Trump said at a joint White House news conference with Trudeau.

However, when asked if NAFTA was addressed at the meeting between the leaders, Morneau said, "We really in much more general terms talked about the importance of the Canada-U.S. trading relationship."

"While I don't have specifics to give you, what I can say is that when you have a relationship as strong and important as ours, between Canada and the United States, it's a great place to start," he added.